Simplify ctx->_NumColorDrawBuffers, _ColorDrawBuffers and fix bug 13835.

These fields are no longer indexed by shader output.  Now, we just have
a simple array of renderbuffer pointers.

If the shader writes to gl_FragData[i], send those colors to the N
_ColorDrawBuffers.  Otherwise, replicate the single gl_FragColor (or
the fixed-function color) to the N _ColorDrawBuffers.

A few more changes and simplifications can follow from this...

2 files changed, 4 insertions, 7 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_fallback.c b/src/mesa/drivers/dri/i965/brw_fallback.c
index 3c4c60a3eab..58aeeb4228c 100644
--- a/src/mesa/drivers/dri/i965/brw_fallback.c
+++ b/src/mesa/drivers/dri/i965/brw_fallback.c
@@ -62,12 +62,9 @@ static GLboolean do_check_fallback(struct brw_context *brw)
    /* We can only handle a single draw buffer at the moment, and only as the
     * first color buffer.
     */
-   for (i = 0; i < MAX_DRAW_BUFFERS; i++) {
-      if (fb->_NumColorDrawBuffers[i] > (i == 0 ? 1 : 0)) {
-	 DBG("FALLBACK: draw buffer %d: 0x%08x\n",
-	     i, ctx->DrawBuffer->_ColorDrawBufferMask[i]);
-	 return GL_TRUE;
-      }
+   if (fb->_NumColorDrawBuffers > 1) {
+      DBG("FALLBACK: multiple color draw buffers\n");
+      return GL_TRUE;
    }
 
    /* _NEW_RENDERMODE
diff --git a/src/mesa/drivers/dri/i965/brw_sf_state.c b/src/mesa/drivers/dri/i965/brw_sf_state.c
index 05c64909495..f083e3148b1 100644
--- a/src/mesa/drivers/dri/i965/brw_sf_state.c
+++ b/src/mesa/drivers/dri/i965/brw_sf_state.c
@@ -43,7 +43,7 @@ static void upload_sf_vp(struct brw_context *brw)
    const GLfloat depth_scale = 1.0F / ctx->DrawBuffer->_DepthMaxF;
    struct brw_sf_viewport sfv;
    struct intel_renderbuffer *irb =
-      intel_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0][0]);
+      intel_renderbuffer(ctx->DrawBuffer->_ColorDrawBuffers[0]);
    GLfloat y_scale, y_bias;
 
    memset(&sfv, 0, sizeof(sfv));